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Techmino/light.lua
2020-02-04 19:36:54 +08:00

80 lines
2.1 KiB
Lua

--LIGHT MODULE(Optimized by MrZ,Original on github/love2d community/simple-love-lights)
--Heavily based on mattdesl's libGDX implementation:
--https://github.com/mattdesl/lwjgl-basics/wiki/2D-Pixel-Perfect-Shadows
local gc=love.graphics
local C=gc.clear
local shadowMapShader=gc.newShader("shadowMapShader.cs")--Shader for caculating the 1D shadow map.
local lightRenderShader=gc.newShader("lightRenderShader.cs")--Shader for rendering blurred lights and shadows.
Lights={}--Lightsource objects
local Lights=Lights
--Private--
local function move(L,x,y)
L.x,L.y=x,y
end
local function setPow(L,pow)
L.size=pow
end
local function destroy(L)
L.blackCanvas:release()
L.shadowCanvas:release()
L.renderCanvas:release()
end
local function draw(L)
local r,g,b,a=love.graphics.getColor()
gc.setCanvas(L.blackCanvas)C()
gc.setCanvas(L.shadowCanvas)C()
gc.setCanvas(L.renderCanvas)C()
lightRenderShader:send("xresolution",L.size);
shadowMapShader:send("yresolution",L.size);
--初始化数据
local X=L.x-L.size*.5
local Y=L.y-L.size*.5
--整束光的左上角
gc.translate(-X,-Y)
L.blackCanvas:renderTo(L.blackFn)
gc.translate(X,Y)
--渲染遮光物
gc.setShader(shadowMapShader)
gc.setCanvas(L.shadowCanvas)
gc.draw(L.blackCanvas)
--根据遮光物渲染阴影画布
gc.setShader(lightRenderShader)
gc.setCanvas(L.renderCanvas)
gc.draw(L.shadowCanvas,0,0,0,1,L.size)
--根据阴影画布渲染光画布
gc.setShader()gc.setCanvas()gc.setBlendMode("add")
--准备渲染
gc.setColor(r,g,b,a)
gc.draw(L.renderCanvas,X,Y+L.size,0,1,-1)
--渲染到屏幕
gc.setBlendMode("alpha")
--复位
end
--Public--
function drawLight()
for i=1,#Lights do
Lights[i]:draw()
end
end
function clearLight(L)
for i=1,#Lights do
Lights[i]:destroy()
Lights[i]=nil
end
end
function addLight(x,y,R,F)
local id=#Lights+1
Lights[id]={
id=id,
x=x,y=y,size=R,
blackCanvas=gc.newCanvas(R,R),--遮挡物画布
shadowCanvas=gc.newCanvas(R,1),--1D视深画布
renderCanvas=gc.newCanvas(R,R),--灯光画布
blackFn=F,--遮挡物绘图函数
--方法
move=move,
setPow=setPow,
draw=draw,
destroy=destroy,
}
end